Heat-exchanger tube for condensing of vapor

In a metallic heat-exchanger tube with integral external fins which extend annularly or helically on an outside of the tube, wherein the fins have a uniform fin height H throughout and a trapezoidally-shaped cross section over a majority of the fin height, wherein the fins have generally axially facing fin flanks with convex edge defining means thereon, and wherein the convex edge defining means include spaced-apart depressions in the fin flanks, each of the depressions being elongated in a radial direction to a specified dimension from a fin tip and increasing in depth in a radially inward direction toward said specified dimension and having a bottom wall contained in a plane parallel to a central plane of the fin and terminating at a radially outer edge flush with a radially outwardly facing surface at the fin tip so as to define a first convex edge at a juncture therebetween, and sidewalls interposed between the bottom wall and the fin flank, a juncture between the sidewalls and the fin flank as well as between the sidewalls and the radially outwardly facing surface at the fin tip forming a second convex edge therebetween.

In a metallic heat-exchanger tube with integral external fins which extend annularly or helically on an outside of the tube, wherein the fins have a uniform fin height H throughout and a trapezoidally-shaped cross section over a majority of the fin height, wherein the fins have generally axially facing fin flanks with convex edge defining means thereon, and wherein the convex edge defining means include spaced-apart depressions in the fin flanks, each of the depressions being elongated in a radial direction from a first specified dimension from a fin tip to a second specified dimension from the fin tip and increasing in depth in a radially inward direction between the aforesaid first and second specified dimensions and having a bottom wall contained in a plane parallel to a central plane of the fin and terminating at a radially outer edge flush with the fin flank so as to define a first convex edge at a juncture therebetween, and sidewalls interposed between the bottom wall and the fin flank, a juncture between the sidewalls and the fin flank forming a second convex edge therebetween.

In a metallic heat-exchanger tube with integral external fins which extend in a generally axial direction on an outside of the tube, wherein the fins have a uniform fin height H throughout and a trapezoidally-shaped cross section over a majority of the fin height, wherein the fins have generally circumferentially facing fin flanks with convex edge defining means thereon, and wherein the convex edge defining means include spaced-apart depressions in the fin flanks, each of the depressions being elongated in a radial direction to a specified dimension from a fin tip and increasing in depth in a radially inward direction toward said specified dimension and having a bottom wall contained in a plane parallel to a central plane of the fin and terminating at a radially outer edge flush with a radially outwardly facing surface at the fin tip so as to define a first convex edge at a juncture therebetween, and sidewalls interposed between the bottom wall and the fin flank, a juncture between the sidewalls and the fin flank as well as between the sidewalls and the radially outwardly facing surface at the fin tip forming a second convex edge therebetween.

In a metallic heat-exchanger tube with integral external fins which extend in a generally axial direction on an outside of the tube, wherein the fins have a uniform fin height H throughout and a trapezoidally-shaped cross section over a majority of the fin height, wherein the fins have generally circumferentially facing fin flanks with convex edge defining means thereon, and wherein the convex edge defining means include spaced-apart depressions in the fin flanks, each of the depressions being elongated in a radial direction from a first specified dimension from a fin tip to a second specified dimension from the fin tip and increasing in depth in a radially inward direction between the aforesaid first and second specified dimensions and having a bottom wall contained in a plane parallel to a central plane of the fin and terminating at a radially outer edge flush with the fin flank so as to define a first convex edge at a juncture therebetween, and sidewalls interposed between the bottom wall and the fin flank, a juncture between the sidewalls and the fin flank forming a second convex edge therebetween.